In high-volume production, it is the price of the end product that matters. Purchasing decisions for production equipment therefore usually boil down to price divided by output modified by some efficiency factor.
However, the number of good products that are really produced is determined by the machine design, line layout, number of machine stoppages and board quality. That is what determines whether you have made the correct purchasing decision. Since unbuffered lines are less efficient than buffered ones, buffering needs to be considered when the line is purchased.
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